/*
 * Copyright 2017 hv0912
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.vimhe.ezimp2.handler.validator.support;

import com.vimhe.ezimp2.handler.validator.AbstractValidator;

import java.util.HashMap;
import java.util.Map;
import java.util.regex.Pattern;

import static com.vimhe.ezimp2.Constants.VALIDATOR_NAME_STRING_PATTERN;

/**
 * 使用指定的正则表达式验证内容
 * <p>注意该验证器可能会极大地消耗性能，在数据量过多的时候不建议使用</p>
 *
 * @author Vimhe
 */
public final class StringPatternValidator extends AbstractValidator<String> {

    /**
     * 为了性能考虑，对编译过的正则表达式进行缓存处理
     */
    private Map<String, Pattern> patternMap = new HashMap<>(16);

    @Override
    public String name() {
        return VALIDATOR_NAME_STRING_PATTERN;
    }

    @Override
    protected boolean validateValue(String cellValue, String configValue) {
        // 从缓存中获取编译过的正则表达式对象
        // 如果存在则直接获取
        // 如果不存在则进行编译并存入缓存中
        Pattern pattern = patternMap.get(configValue);
        if (pattern == null) {
            pattern = Pattern.compile(configValue);
            patternMap.put(configValue, pattern);
        }

        return pattern.matcher(cellValue).matches();
    }

}
